Chem 14CL Summer 05 8 - The Determination of the Concentration and Acid Dissociation Constants of an Amino Acid Pre-lab and Post-lab reports MUST be written inside your lab notebook. Refer to the lab schedule for due dates of both the post-lab and the pre-lab. Type written reports will NOT be accepted (with the exception of graphs). On line Technique and Resources For This experiment Click on the title below to download the video (require Real Player) (1) Laboratory Safety (this video was shown on the first day of the lab) (2) Solution Preparation (3) Use of a Buret If you have trouble downloading the videos, go to the following Web site and click on the appropriate title to download the video. http://oid.ucla.edu/Webcast/Chemistry/ Guides for Writing Lab Reports On-line resource for acid-base chemistry IMPORTANT: You should review the concepts of acid-base chemistry from 14A, 14BLand from the on-line tutorials listed here for this experiment. Pre-lab Report Guidelines For Lab Period #1 Pre-lab report is due at the beginning of the lab section. Pre-lab report MUST be written inside your LAB NOTEBOOK. This experiment consists of THREE separate pre-lab reports. Due date for each part of the report is listed on this guideline. Lab period 1 pre-lab report is due on Wednesday 6/29 (I) Introduction - write down the goal(s) of the ENTIRE experiment as well as the experimental techniques that you will be using in order to achieve such goal(s). (II) Construct flowchart of procedures for ONLY the following parts of the experiment • Preparation of the Standard TRIS Solution (Primary Standard) • Standardization of the HCl Solution (Secondary Standard) • Standardization of the NaOH Solution (Secondary Standard) (III) Set up blank data tables (Start a NEW page for this part) for the 3 parts of the experiment that outlined in (II)Chem 14CL Summer 05 8 - The Determination of the Concentration and Acid Dissociation Constants of an Amino Acid Pre-lab is due at the beginning of the lab section. Pre-lab report MUST be written inside your LAB NOTEBOOK. Pre-lab Report Guidelines For Lab Period #2 Lab period 2 pre-lab report is due on Thursday 6/30 (I) Construct flowchart of procedures for ONLY the following parts of the experiment • Titration Analysis of the Unknown Amino Acid with HCl (refer to page 97) • Titration Analysis of the Unknown Amino Acid with NaOH (refer to page 97) Cite the reference for the procedures. (II) Study Questions Complete questions 1,2, &3 under “PERIOD 1” (Refer to pages 94 & 95) You MUST show all the calculations and work in order to receive full credit. Read pages 90-94 BEFORE attempting to complete the study questions. NOTE: Question 3 (see page 94) should read 3.29 ml of HCl and 18.61 ml of NaOH. For the HCl, you may assume that the 3.29mL corresponds to the first inflection point volume. The pKa’s for the amino acid in question #4 can be determined based on the information given in question #3. Hint: For question #3, assume that the 10-ml of unknown solution contains both the A & A- forms of the amino acid. Refer to the lab manual for the structures of the A, and A- forms of the amino acid. Pre-lab Report Guidelines For Lab Period #3 Lab Period 3 Prelab is DUE on Friday 7/1 Complete study question 1b ONLY under the section "Period 2" (Refer to page 95). Hint: Sketch the titration graph by calculating the pH at the following points on the titration graph. 0mL, 5mL, 10mL, 15mL, 20mL, 25mL, 30mL & 40mL of HCl You MUST show all work for full credit) NOTE THAT ALL pK IN THE PROBLEMS ARE pKa and not
View Full Document
Unlocking...